Fast Probabilistic Load Flow for non-radial Distribution Grids

To ensure the smooth operation of a distribution grid with a high share of renewable energies, it is important to know the state of the grid at all times. Especially in cases when bus power measurements or estimates are uncertain, the resulting voltage probability distribution is important to assess the situation. This is done using probabilistic load flow methods such as Monte-Carlo simulations. To reduce computational load, a method for a simplified calculation of the probabilistic load flow for grids with a radial structure has been published by the author. This paper extends the algorithm to work also with non-radial grid structures and compares the performance of the calculation at different load scenarios in terms of estimation accuracy and calculation time. It is shown, the extension performs similar compared to the radial grid approximation with an only minor increase in computational load. Keywords—smart grids, power system control, power grids, probability distribution.